With the development of wideband communication technology, a variety of video services are being provided using communication technology. For example, not only various pieces of image information may be obtained using a computer over the Internet, but also broadcasting service of a high picture quality may be used using a mobile phone.
In this service environment, there is an increasing demand for using an image of a high picture quality through high-speed data transmission and thus there is an increasing interest in an image compression technique.
The image compression technique is for representing an image into a small amount of digital data as possible, while maintaining an original picture quality, by removing some pieces of dispensable information while maintaining important information included in an original image.
In the image compression technique, in order to reduce data for representing an image, a target coding picture (frame) may be coded for each block which is composed of a plurality of pixels. Furthermore, in the image compression technique, a block may be divided and coded in order to increase the picture quality.